The old " Roloffia/Aphyosemion maeseni turned out to have been described from a type specimen that was really an Epiplatys. This is the new name for that fish.
Discovered in 1995 by W. Suijker and Y. Suijker-Jansen who also found another location 1997 with F. and M. Vermeulen; no other locations have been found since. Described by W. Suijker and G. Collier in 2006. Unusually low number of chromosomes with a rather large pair of arcocentric elements (shown with arrows). Uneven sex ratios are common, not difficult otherwise. From cool acidic soft "black" water similar to African killifish blackwater biotopes for example, Diopteronspecies.
Lacustricola margaritatus, a new species inhabiting small streams and swamps in the Lake Victoria basin in north-western Tanzania and southern Uganda, and the Lake Kyoga basin in central Uganda, is described. Lacustricola margaritatus is a small species with a moderately deep body, moderate dimorphism and pronounced dichromatism. It is distinguished from all other Procatopodidae by the following unique combination of characters: live male body colour pattern with vertically-elongated iridescent light blue patches at scale centres, forming a striped appearance of dotted longitudinal lines on the flanks, particularly evident in the two or three series below the mid-longitudinal line; male having deeply coloured unpaired fins with orange-brown in the proximal and median parts and a narrow black distal band; male with a yellow base along the pectoral fin; female with dark grey scale margins and dark grey patches on scales along mid-longitudinal series creating a narrow dark grey stripe; both sexes showing inconspicuous postopercular blotch; and in both sexes, the cephalic sensory system is entirely situated in open grooves at all levels. The new species has previously often been misidentified as L. pumilus, originally described as inhabiting the Lake Tanganyika basin in north-eastern Zambia, or 'L.' centralis, from the Lake Rukwa basin in south-western Tanzania. Lacustricola margaritatus differs from the above two species by morphometric and meristic characters, body and fin colouration, and in arrangement of the cephalic sensory system.
"Aphyosemion mitemelense can be distinguished from both described species of the ‘A.’ herzogi species group by the male colour pattern of body and unpaired fins. In A. mitemelense the caudal fin has several more or less horizontal relatively wide dark red bands on centre and lower part of fin vs. whole fin with many red interradial lines on blue centre and lower part of fin in ‘A.’ bochtleri and two red lines edging a broad yellow band on fin centre in ‘A.’ herzogi. Background of anal fin green to blue green in A. mitemelense vs. yellow to orange, at least basally, in the other two species.
Aphyosemion mitemelense can be distinguished from neighboring undescribed species from the ‘A.’ herzogi group by having a greenish appearance and a green anal fin with irregular red blotches and/or stripes and a large dark red spot at the base of pectoral fin vs. a reddish appearance and an orange anal fin with regular interradial lines and lacking a red spot at the base of pectoral fin in populations on the right bank of the Mitemele River in southern Equatorial Guinea; by lacking a yellow horizontal band at the base of anal fin vs. having such a band in a population that occur sympathetic near the village of Mveayong in the extreme southeast of Equatorial Guinea. Aphyosemion mitemelense differs from populations between Ngolensok and Acurenam in southeastern Equatorial Guinea by absence of more or less regular red interradial lines in caudal fin centre, lower half of caudal greenish versus yellow and upper part of fin with many irregular red spots versus most part of upper half of caudal fin with red interradial lines; it differs also by the presence of broad red blotches, stripes or bands on greenish or blue-greenish anal fin versus more narrow, short red interradial lines on yellow or orange anal fin."
P17-18 "Three New Killifish Species (Cyprinodinriformes: Nothobranchiidae) From Equatorial Guinea" (PDF), Francisco J. Malumbres, Rainer Sonnenberg & Jouke R. Van der Zee, Oct 2022
